The present invention relates to producing CO.sub.2 from subterranean reservoirs for use at high pressures. More particularly, the invention relates to an improved process for preventing hydrate formation in CO.sub.2 -containing fluids being flowed from the producing wells to a CO.sub.2 dehydrating facility.
U.S. Pat. No. 4,235,289 describes the production of CO.sub.2 from subterranean wells for use at high pressure and recommends that the CO.sub.2 be maintained in a substantially single phase supercritical state; but also indicates that a hydrate inhibitor or drying agent, e.g. ethylene glycol may be added to prevent hydrate formation from damaging the gathering line.
U.S. Pat. No. 3,676,981 describes treatment of natural gas at superatmospheric pressure and states that, with respect to such hydrocarbon gases, glycols and methyl alcohol have been found to be "the most effective hydrate inhibitors".
U.S. Pat. No. 4,478,612 by Zaida Diaz and J. H. Miller describes a process for drying at least substantially supercritical CO.sub.2 with glycerol and indicates that the anomalous solvency properties of CO.sub.2 near or above its critical point are such that significant savings can be attained by using glycerol as the desiccant at a relatively low temperature in order to minimize the energy required for compressing the dry CO.sub.2 for use at high pressure. The disclosures of U.S. Pat. No. 4,478,612 are incorporated herein by reference.